1. Field of the Invention
The present invention relates to an information displaying device, and in particular, to an information displaying device which displays information, from among multidimensional information, which corresponds to a given displayed region within a cross-section with respect to two predetermined dimensions.
2. Description of the Related Art
A display, such as a CRT or a liquid crystal display, is provided as a means for transmitting information to a user at an information processing device such as a computer. Information is supplied to the user through images, characters, or the like being displayed on the display. The size of the display surface of the display is limited. Since a displayable area is limited to the physical size of the display, only a portion of the information can be displayed on the display, and a plurality of icons for designating various, different directions of change (scroll) is displayed. When it is desired to change the displayed region, the user operates a mouse or the like, moves a cursor in the display to an area at which the icon corresponding to the desired direction of change is displayed, and selects the icon. In this way, the displayed region changes on the image, and scrolling of the displayed image is effected.
In fields such as scientific/technological calculation or the like, results of calculation are converted into image data and are displayed in order to facilitate comprehension of the contents of the results of the calculation. Such data is often multidimensional data of three or more dimensions. For example, data may represent dynamical changes of the flow of a two-dimensional fluid, which is projected on a two-dimensional plane, over time (the two-dimensional fluid data+time=three dimensions). Because only a two-dimensional cross-section can be displayed on the display, the display for this type of multi-dimensional data is effected as follows. The third dimension, other than the two which specify the cross-section, is regarded as a new parameter, and a plane at a predetermined value of the new parameter is displayed (e.g., when the new dimension is the time dimension, the plane at a certain time is displayed). The value of the new parameter is changed in accordance with the designation of the user, and the direction of change of the displayed region is switched.
When the value of the parameter corresponding to the new dimension is changed (the direction of change is switched) and the displayed region is changed, conventionally, a plurality of icons for designating changes in directions corresponding to the new dimension are displayed (e.g., when the new dimension is time, the past direction and the future direction). Designation is effected by selecting the icon corresponding to the desired direction. However, generally, the amount of multidimensional data is extensive. In order to retrieve and display a desired portion of the multidimensional data, the changing of the displayed region and the switching of the direction of change are repeated while a portion of the multidimensional data is displayed. Each time the direction of change is switched, the cursor must be moved to another icon. Therefore, work efficiency deteriorates.
Further, as another example of designating scrolling, Japanese Patent Application Laid-Open No. 1-179193 discloses a scrolling method in which the scrolling speed is variable, and the scrolling direction and the scrolling speed can be designated by a single icon. In this scrolling method, the scrolling speed is determined by the distance of the location of the cursor in the icon from a reference point of the icon. The scrolling direction is determined by the position of the cursor with respect to the above-mentioned reference point. Even if the cursor is to be greatly moved, scrolling at an arbitrary speed and in an arbitrary direction can be effected. However, this method is used only to change the displayed region within a plane and does not take into consideration change in a direction corresponding to another dimension. Therefore, workability is low when multidimensional data of three or more dimensions is treated.